Depression and Pain Can Reduce Efficacy of Treatment for the Other

LAS VEGAS—Major depression is pervasive among pain clinic patients, with reported rates varying from clinic to clinic but commonly exceeding 50%, compared to 4% among the general population. But treating major depression in the context of pain is a complex challenge, said Mark D. Sullivan, MD, PhD, Professor  of Psychiatry at the University of Washington.

Worldwide and across cultures, the WHO reports that patients with persistent pain (>6 months) are 4.14 times more likely than others to have anxiety or depressive disorder. Pain can cause depression but treatment of pain does not necessarily make depression vanish, Dr. Sullivan reported at PAINWeek 2014.

Among patients receiving chronic opioid therapy, depression was the strongest predictor of ambivalence about opioids. “Depression reduces response to pain treatment,” he said. “Acute pain is lessened with opioid treatment but depression is associated with reduced response to acute opioid treatment. Depression complicates pain treatment, but the converse is also true: chronic pain reduces responses to depression treatment, further complicating treatment.

The risk of poor SSRI (selective serotonin reuptake inhibitor) treatment response in those with mild pain is 25%, he noted; 30% among patients with moderate pain, and 14% among patients with severe pain. Antidepressants with norepinephrine reuptake inhibition like TCAs (tricyclic antidepressants) and SNRIs (serotonin–norepinephrine reuptake inhibitors) are better analgesics than other antidepressants, Dr. Sullivan said. These are “clearly preferred for neuropathic pain and probably preferred for musculoskeletal pain,” he noted.

Depression with chronic pain is frequently complicated by post-traumatic stress disorder (PTSD) or anxiety, substance abuse, and occasionally, borderline personality disorder, Dr. Sullivan said. Antidepressants with serotonin blockade, like trazodone, nefazodone, or mirtazapine, are associated with better sleep and anxiety, and are better tolerated among patients with PTSD or panic symptoms.

Patients suffering from depression and pain also frequently have trauma issues, often from childhood. “This trauma needs to be recognized and addressed before depression treatment can succeed,” he emphasized.

“Emphasize that depression treatment will help other pain treatments work better.” If patients report that antidepressants make them feel worse, providers should carefully explore what that means rather than dismissing— or accepting—such statements at face value, he said. “It can mean ‘I felt the clinician was ignoring my pain, or ignoring me, and writing the prescription to get me out the door',” he explained. Or it might mean “the antidepressant made me more anxious, more angry, more depressed.”

“Don't oversell antidepressants” to patients, he concluded. “They are imperfect medications with side effects.” Instead, providers should encourage patients to “put their nickel down” by participating in the selection of a treatment from among the available options. “If they are invested in the choice of treatment, they are less likely to reject the treatment,” he said.